Tractor



May 28, 1935.

TIE-E N. LESSER TRACTOR Filed Jan. 1'7, 1934 3 She'etS-Sheet 1 May 28,1935. NF LESSER 2,002,669

TRACTOR Filed Jan. 17, 1934 3 Sheets-SheetV 2 [NI/ENTOR A TT ORNE YS.

May 28, 1935. N, LESSER 2,002,669

TRACTOR Filed Jan. 17, 1934 5 sheds-sheet s 'Z' |25 lZO I5! I 55h;Cl iyZ 9 b 9 b lll 52 I |5015@ Patented May 28, 1935 PATENT OFFICE TRACTORNathan Lesser, Moline, Ill., assignor to John Deere Tractor Company,Waterloo, Iowa, a

corporation of Iowa Application January 17, 1934, Serial No. 706,935

17 Claims.

'Ihe present invention relates to tractors having power take-offmechanism arranged to operate implements associated withthe tractor andalso arranged to raise and lower tools and per- 5 form other or similarservices in connection with such implements.

One of the principal objects of the present invention is the provisionof novel means for delivering power from the relatively high speed powertake-off shaft to the relatively low speed lifting crank or other meansfor raising or lowering the implement tools and the like. Anotherimportant object of the present invention is to effect the desired speedreduction by the use of epicyclic mechanism which is arranged in acompact manner on the tractor and is less expensive and longer livedthan the usual type of speed reduction means in use at the present time.

Another important object of the present invention is the provision ofimproved supporting means for the bearings of the epicyclic gearingmechanism, by virtue of which the parts may be supported on the tractorsimply and sturdily and with the minimum requirement for space.

Still further, another important object of the present invention is theprovision of new and useful means for interrupting the transmission ofpower through the speed reduction mechanism in accordance with theextent of rotation of the driven part or parts.

These and other objects of the present invention will be apparent tothose skilled in the art after a consideration of the following detaileddescription of a preferred structural embodiment, taken in connectionwith the accompanying drawings illustrating such embodiment.

In the drawings:

Figure 1 is a rear elevation of a portion of the tractor with the powerlift parts being shown in a section taken along the line I-I of Figure6;

Figure 2 is a horizontal section taken along the line 2-2 of Figure 1;

Figure 3 is a side view looking toward the left side of the rear end ofthe tractor;

Figure 4 is a section taken along the line 4-4 of Figure 1;

Figure 5 is a section taken along the line 5-5 of Figure 1;

Figure 6 is a section taken along the line 6-6 of IFigure 1;

Figure '7 is a fragmentary section, illustrating a portion of theoptionally controlled clutch mechanism; and

Figure 8 is a diagrammatic view illustrating certain of the geometricalprinciples employed in the present invention.

Referring now to the drawings, the farm tractor to which the presentinvention is preferably applied is of conventional construction wellknown in the art and is of the type embodying a rear axle housing I ofthe kind generally referred to as of the banjo type and including agenerally cylindrical central section 2 and tubular housing sections 3in which driving axle shafts 4 are journaled. The farm tractor includesmotor driven mechanism for driving the axle shafts 4, and this mechanismis usually provided with differential means disposed within the centralhousing section 2 and driven by shaft means (not shown) connectedthrough suitable transmission gearing with .the motor of the tractor.

The power lift mechanism of the present invention is supported by andenclosed within a housing Il bolted, as by cap screws I2, over the rearopening of the central section 2 of the rear axle housing I of thetractor. The power lift mechanism housing II includes a flanged sectionI3 receiving the bolts I2, and formed integral with the housing II is acylindrical portion I5 disposed generally transversely with respect tthe tractor and open at both ends, as best shown in Figures 1, 2 and 4.

The tractor is one which is adapted for driving various implementmechanisms which may be associated therewith, and to this end, I providea longitudinally extending power take-olf shaft I6 journaled in abearing I'l which is supported in an inwardly extending tubular bearingsupporting boss I8 preferably formed integral with the rear wall of thecylindrical section I and extending forwardly therefrom near the middleof the wall, as best indicated in Figure 2. The rear end of the powertake-off shaft I6 is provided with any suitable means (not shown), suchas a universal joint, by which the implement mechanism or the shaftmeans thereof may be connected to be driven by the motor of the tractor,and the forward end of the power take-off shaft I6 is connected in anysuitable manner with the driving mechanism of the tractor.

The two outer ends of the cylindrical portion I5 are closed by means ofcaps 20 and 2|, and these caps are suitably fixed to the cylindricalhousing I5 by suitable means, such as cap screws 22. The left hand cap20 is provided with a relatively long `bearing sleeve 25, best shownin.Figures 1 and 2, and journaled in this bearing supporting sleeve,which is preferably formed integral with the cap 20, is a crank shaft 26having splines 21 and 28 at the opposite ends thereof. The crank shaft26 is provided with a lubricant hole 30 intermediate the bearings 29.The outer end of the crank shaft 26 extends outside the cap 20 and has acrank 3| secured thereto, as by a washer and cap screw assembly 83. Thecrank 3| carries a crank pin 35 which receives one end of a thrust rod36, the other end of which is pivoted, as at 38 (Figure 3), to one endof an arm 40 fixed on a lifting rock shaft 4| journaled in bearings 42supported in any suitable manner on the tractor. The lifting rock shaft4| is adapted to be operatively connected with implement tools or thelike for raising and lowering or otherwise controlling the position ofthe latter.

The lifting crank shaft 26 is adapted to be driven from the powertake-off shaft |6 by suitable gear reduction means and suitablecontrolling clutch means which will now be described.

The other cap 2| is provided with an inwardly extending bearingsupporting sleeve 50 in which is disposed a bearing 5| which serves tosupport the outer end of a jack shaft 52. The inner end of the jackshaft 52 is supported by bearing means 53 carried in a forward extension54 which is preferably formed integral with the inwardly extendingbearing sleeve |8 carried by the rear wall of the cylindrical housingsection |5, as best shown in Figures 1 and 2. The forward extension orbearing supporting collar 54 is reinforced by suitable flanges 55preferably formed integral with the extension 54 and the yoke bearingsupporting sleeve I8.

'Ihe jack shaft 52 is driven by means of a. suitable power connectionwith the power takeoff shaft I6, which power connection preferablyincludes an optionally controlled clutch of thel self interrupting typeindicated in its entirety by the reference numeral 59. For this purposethe power take-off shaft I6 is provided with a bevel gear 60 suitablykeyed or otherwise fixed thereto, and the bevel gear 60 meshes with acompanion gear 6| mounted on the flanged section 62 formed on a sleeve63 journaled on the jack shaft 62 adjacent the inner end thereof butbetween the bearings 5| and 53 for the jack shaft. Preferably, the bevelgear 6| is fixed to the flange 62 by means of suitable cap screws 65, asbest shown in Figure l. The jack shaft 52 is splined adjacent the outerend thereof, as indicated at 61, and slidably mounted on this splinedsection is a shiftable sleeve 18 having a radially outwardly extendingflange 1| disposed adjacent the flanged section 62 of the sleeve 63.

The sleeve 10 is provided with internal splines engaging the splines 61,whereby the sleeve 10 rotates with the jack shaft 52. The sleeve 10 isfree to slide axially with respect to the jack shaft 52 and is providedwith a tapered lug 15, preferably formed integral with the iiange 1| andextending in a generally axial direction, as best shown in Figures 1, 4and '1. The flange 62 carries an axially extending rim 16 formedintegral therewith, and within this rim is an expansible split ring 11,the ends of which are beveled, as best shown in Figure '7, and aredisposed adjacent the tapered lug 15 to be engaged thereby whenever thesleeve 10 is moved inwardly, to the left as viewed in Figures 1, 2 and7. The lug 15 acts against the bevel ends of the ring 11 to expand thesame against the rim 16 carried by the sleeve 63 which, in turn, carriesthe bevel gear 6|. Thus, the driving force is transmitted from the powertakeoff shaft I6 through the gears 60 and 6| to the sleeve member 63,and from this member the power is transmitted through the splined member10 to the jack shaft 52. The expansible split ring 11 is resilient sothat when the tapered lug 15 is withdrawn the ring 11 contracts inwardlyout of engagement with the rim 16.

The means for controlling the axial shifting movements of the splinedsleeve 10 for governing the application of power to the Jack shaft 52will now be described. Th/e mechanism for sliding the sleeve 10 upon thejack shaft 52 comprises a pair of ring members and 8| which arejournaled upon the sleeve member 10. These sleeve members 80 and 8| arebest shown in Figure 4, from which figure it will be observed that thesemembers are provided with a series of opposed cam surfaces 83 and 84 ofsuch a nature that relative rotation of one member with respect to theother causes them to separate in an axial direction. The ring memberV 8|has a circular plate 85 preferably formed intef gral therewith and isnormally held against three spaced lugs 86 which are formed integralwith the cap 2| by a coil spring 88 which bears against the back of theplate 85 and against the end of the cap 2|, as clearly shown in Figures1, 2 and 4. The plate 85 is held against rotation by pins 90 disposed inslots formed in the edge of the plate 85, and the pins are long enoughto permit a certain amount of axial movement of the plate 85.

The ring member 80 is provided with an arm 92, preferably formedintegral therewith, and in the end of the arm 92 a slot 93 is provided,as best shown in Figure 5. A vertically disposed plunger |00 is slidablymounted inthe housing and is disposed in a boss |0| and extends at itsupper end through an opening in a vertically disposed cylindricalhousing section |02. The lower end |03 of the plunger |00 carries a boltor pin |04 which is disposed within the slot 93 at the outer end of thearm 92. bears at its lower end against the boss |0| and at its upper endagainst a key or pin |08 carried by the plunger |00. Thus, the spring|06 serves to hold the plunger in its upper position, that shown inFigure 5, which disposes the arm 92 in its upper position.

By stepping on or otherwise depressing the plunger |00 against thetension of its spring |86, the ring member 80 will be rotated relativeto the companion ring member 8|, and this, in turn, will cause the tworing members to separate. The ring member 80 bears against the flange1|, while the ring member 8| bears against the spring 88, and as aresult of this arrangement the pressure of the spring 88 will cause thesleeve member 10 and the tapered lug 15 to be shifted axially toward theleft as viewed in Figures 1 and 7. This forces the tapered wedge 15 inbetween the ends of the expansible ring 11, causing the latter tofrictionally engage the rim 16 and establish a driving connectionbetween the power take-off shaft |6 and the jack shaft 52 as describedabove. During this clutching engagement, the plate member 85 is adaptedto have a limited amount of A spring |06 surrounds the plunger |00 andaxial .movement on the pins $0.. -Thus, .whenever the plunger isdepressed, a driving connection is established between the powertake-off shaft l and the jack shaft 52.

The jack shaft 52 is operatively connected with the crank shaft 26 torotate the latter by means of a speed reducing eplcyclicgearingmechanism which provides the desired gear reduction for operating toolor implement` lifting mechanism, the speed of movement of 4which isrelatively low, from the power take-ofi' shaft, which normally rotatesat an appreciable rate.

The epicyclic gearing is best shown in Figures 1 and 2. An externalbevel gear |20 is mounted on the inner splined end 28-of the crank shaft25 and an internal bevel gear |2| is adapted to vhave one portion inmesh with the bevel gear |20 and is securely xed, as by cap screws, to arocking or gyratory member |23. The member |23 is supported for gyratorymovement in the casing I5 by means serving as a gimbal or universaljoint to accommodate the rocking movement ofthe member |23 but l.whichis so constructed and arranged that rotation of the member |23 about itsown axis is prevented. The universal joint support isindicated by thereference numeral |30 `and comprises a ring |3| journaled on axiallyaligned pivotpins |32 and |33 having .threaded portions screwed intothreaded bosses |35 formed on the housing |5 as best shown in Figure 6.Thus, the ring member |2| is capable of rocking movement about an axis,defined by the pins |32 and |33, which is inclined upwardly andrearwardly with respect to the tractor. The ring member.V |3| carries atransverse pin |31 disposedl with its axis disposed at right angles tobut in the same plane as theaxis of the pins |32 and |33. A member |38is rockably mounted on the pin |31 and is thus capable of movement aboutan axis disposed at right angles to the axis of movement of the member|3| on which the member |38 is supported in the casing l5. The member|38, in effect, constitutes a part of the gyratory member |23 andserves, in connection with the pivots |32 and |33 and the pivot |31, todefine a point about which the member |23 swings as a center. In Figure8, which will be referred to later and which is a diagrammaticillustration of the geometric principles involved, thisv point or centeris indicated by the reference numeral |40 and lies at the intersectionof the lines shown. This universal joint connection |30 between themember |23 and the housing ||5, while holding the member |23 and thegear |2| fixed thereto against rotation about its own axis, permits themember |23 to have limited rocking orgyra-tory movement about the center|40. From Figure 8 it will be observed that the crank shaft 24 and thejack shaft 52 are in axial alignment and that the point |40 lies intheir common axis. The inner ends of the crank shaft 24 and the jackshaft 52 are spaced apart to accommodate the gyratory member |23 andassociated parts. Since the point |40, about which the member `|23rocks, lies in the common axis of the shafts 24 and 52, the member |23is thus capable of limited rocking movement about any axis which isperpendicular to the common axis of the shafts 24 and 52. l

Thrust washers |4| are interposed between the member |38 and the ringmember |3|, and cotter keys |42 are inserted in suitable openings in thepin |31 and cooperate with the member |3| in 'retaining the pin |31 inposition.

porting means |8-54 forI the rear end of the power take-oil shaft I6 andthe inner endpf the jack shaft 52. From Figure 8 itwill be noted thatthe axis of the cylindrical portion |50 extends at an angle with respectt o the axis of the jack shaft 52 and intersects the common axis of theshafts 24 and 52 at point |40 This point also marks the apex of thepitch cones of the bevel gears |20 and |2|. In Figure 8 the pitch coneof the gear |20 is indicated at a and the pitch cone for the larger4bevel gear |2| is indicated by the reference character b.` vThe point|40 lies at the common apex of the pitch cones a and b of the bevelgears |20 and` |2=|, and this point lies in the transverse plane of theaxes of the pins |32 and |33 and the pin |31.

As a result of these relationships, the rotation of the jack shaft V52,carrying with it theeccentric |50, will cause the common axis |55.(Figure 8) of the bevel gear |2I, the gyratory member |23 and theeccentric |50, to generate a right circular cone, the axis of which conelcoincides with the common axis |55 of the shafts 24 and 52 and the gear|20. The crank throw of the eccentric |50 is such that the includedangle of the right circular cone generated by the -axis |55 is equal tothe difference between the included angles of the pitch cones of thebevel gears |20 and |2|.

By virtue of the above relationships, proper and uniform depth of toothengagement around the entire periphery of the bevel gears |20 and |2| issecured, and each time the gear |2| is caused to generate one cone, thegear |20 will be forced to rotate an amount which is proportional to thedifference between the number of the teeth on the gears |20 and |2I. Forexample, if gear member |20 is provided with forty teeth and the gearmember |2| is provided with fortytwo teeth, the gear |20 and the crankshaft 24 .will be rotated 1/20 of a revolution, and in this case thegear reduction between the crank shaft 24 and the jack shaft 52 is 1 to20. Thus, as long as the plunger |00 is held depressed to causeseparation of the ring members 80 and 8|, the clutch is held inoperative engagement and power is transmitted from the power takeoffshaft I6 to the power lift crankA 26 at a ratio which depends upon thegears 60 and 6| and the ratio established by the epicyclic gearreduction described above.

Means have been provided for automatically holding the clutch inengagement, even after the plunger |00 is released, until the crank 26has completed a half revolution. This mechanism comprises a rod slidablybut non-rotatably mounted in lugs I 1| and |12 (Figure 1) formedintegral with and depending from the upper portion of the housing l5.The rod |10 is provided at one end with an arm depending therefrom andxed thereto, and at the other end another arm |16 is fixed to the rod. Akey |18 or the equivalent, cooperating with the lug |12, serves toprevent rotation of the rod |10 about its own axis and thereby holds thearms |15 and |18 in the desired position. The externalbevel gear |20 isprovided with a pair of diametrically opposed cams and |8|, as bestshown in Figure 1, and these cams are arranged to engage, one at a time,the arm |16 for normally holding -the rod |10 in the position shown inFigure 1. A spring |85, disposed between the lug |1| and a washer |86held in place by a pin |86a, serves to bias the rod |10 for movementtoward the right as viewed in Figure 1.

A radially extending plate sector |81 is formed integral with the ringmember 80 of the clutch, as best shown in Figure 5, and this platesector |81 is provided with a slot |88 therein which is adapted to bebrought into alignment with the lower end of the arm |16 on the rod |10whenever the plunger |00 is depressed to swing the ring member 80 in acounter-clockwise direction, as best seen in Figure 5. It will beremembered that depressing the plunger |00 causes the ring members 80and 8| to separate, thus engaging the clutch and connecting the jackshaft 52 to be driven by powei` from the power take-off shaft I6. Asexplained above, the rotation of the jack shaft 52 causes the gyratorymember |23 to impart a relatively slow rotation to the crank shaft 26,and as soon as the crank shaft 26 rotates a slight amount, the cam |8|(Figure 1) on the gear |20, or the cam |80 if the crank shaft 26 is in aposition |80 degrees from the position shown in Figure 1, is moved outof the path of the arm |15. The spring |85 then shifts the rod |10 tothe right, as viewed in Figure 1, and causes the arm' |15 to engageparts. It is not essential to the present invention that the power liftmechanism operate a lifting rock shaft 4| for, if desired, implementtools or other parts to be raised and lowered can be connected directlywith the crank. 3|.

The plate 85 embracing the slidable -clutch member 10 is provided withthree spaced notches to facilitate assembling the clutch member inposition. To mount this member, the plate 85 is positioned with thenotches |80 aligned with the lugs 86 carried on the cap member 2|. Thespring 88 is disposed between the plate 85 and the back of the cap 2|,and then the plate 85 is forced against the tension of the spring 88until it has been moved past the lugs 86. Then the plate 85 is rotatedabout its own axis to the position shown in Figure 5, after which thepins 80 are screwed in position, the ends thereof engaging in thenotches or slots provided in the plate 85 for their reception.

An important feature of the present invention lies in the fact that if apurchaser does not wish the power lift mechanism at the time hepurchases the tractor but does wish a power take-off shaft, the coverplate casting together with the bearing portion I8 for supporting thepower take-off shaft, can be provided and all of the other partsconstituting the power lift mechanism can be omitted. In that case,sheet metal covers or the like will be provided over the openings inwhich the caps 20 and 2| are ordinarily received. If subsequently thepur- Echaser desires to add the power lift to the tractor, the partsconstituting the lift mechanism and including the caps 20 and 2| can bereadily in the slot |88 (Figure 5), and lthe engagemeniafurnished andDlaCed in Position.

of the arm |16 in the notch |88 effectively prevents the rotation of thering member 80 back to the position shown in Figure 5, even though theoperator releases the pressure on the plunger 00. The driving engagementbetween the power take-off shaft I6 and the jack shaft 52 isconsequently maintained and the crank shaft 26 continues to rotate, butthe continued rotation of the crank shaft 26 serves to advance theopposite cam |88 toward the arm |15, and as the 'crank shaft 26approaches a position |80 degrees from the position shown in Figure 1,the cam |80, which is shaped similar to the cam |8I, bears against thearm |15 and gradually shifts the rod |10 toward the left as viewed inFigure 1. As soon as the rod |00 is moved to the left to a positionwhere the arm |16 will disengage from the notch |88, the spring |06,acting through the plunger |00, will rotate the clutch member 80 back tothe position shown in Figure 5, thus interrupting the transmission ofpower from the power take-off shaft i6 to the jack shaft 52.Consequently, no further rotation of the crank shaft 26 can take placeuntil thev plunger |00 is again depressed.

No special locking means for holding the crank shaft 26 in either of itstwo positions need be provided because the epicylic gear reductionmechanism described above is irreversible and therefore self-locking. Itis, further, to be understood that more than two cams |80 and |8| may beprovided on the bevel gear or on the crank 26, or if desired only onecam may be provided. In the former case, the crank 26 will be rotatedsomewhat less than a half revolution, while in the latter case the crankwill make one complete revolution before the transmission of power tothe jack shaft is interrupted by the operation of the rod |10 andassociated While I have described above the preferred structure in whichthe principles of this invention have been embodied, it is to beunderstood that my invention is not to be limited to the specific meansshown and described, but that, in fact, widely different means may beemployed in the practice of the broader aspects of my invention.

What I claim, therefore, and desire to secure by Letters Patent is: V

1. An epicyclic gearing transmission mechanism comprising, incombination, an external bevel gear, a member including an internalbevel gear having a greater number of teeth than said external bevelgear, means supporting said member to position said internal bevel gearto engage said external bevel gear, said supporting means also beingarranged to hold said member against rotation about its own axis, andmeans for causing said member to move so that the axis of said internalbevel gear generates a right circular cone the axis of which conecoincides with the axis of said external bevel gear.

2. An epicyclic gearing transmission mechanism comprising, incombination, an external bevel gear, a member including an internalbevel gear having a greater number of teeth than said external bevelgear, means supporting said member to position said internal bevel gearto engage said external bevel gear with the apex of the pitch cone ofthe internal bevel gear coincident with the apex of the pitch cone ofthe external bevel gear, and holding said member against rotation aboutits own axis, said supporting and holding means comprising a gyratorymember to which said internal bevel gear is Secured, a ring membermounted for rocking movement about a generally transverse axis, andmeans supporting said gyratory member on said ring member for rockingmovement about an axis disposed 90 degrees in a transverse directionfrom said first axis, and means for causing said gyratory member to moveso that the axis of said internal bevel gear generates a right circularcone the axis of which cone coincides with the axis of vsaid externalbevel gear and the apex of which coincides with the apices of the pitchcones of y said bevel gear.

3. An epicyclic gearing transmission mechanism comprising, incombination, a housing, a pair of axially aligned driving an drivenshafts journaled in said housing, an external bevel gear fixed adjacentthe inner end of one of said shafts, a gyratory member including aninternal bevel gear having a greater number of teeth than said externalbevel gear, supporting means carried by said housing and supporting saidgyratory member so as to position said internal bevel gear to engagesaid external bevel gear, said supporting means holding said gyratorymember against rotation about its own axis, a pair of spaced generallyaxially extending arms carried by said gyratory member, a collar at theends of said arms, an eccentric carried adjacent the inner end of theother of said shafts and journaled in said collar, a driving shaftextending between said arms and extending at an angle to the axis ofsaid aligned shafts, and means operatively connecting said driving shaftwith one of said first-named shafts.

4. A power lift mechanism comprising a shaft, means for optionallyrotating said shaft, a crank shaft, an epicyclic gearingtransmission'mechanism connecting said shafts, said mechanism comprisingan external bevel gear on said crank shaft, a member including aninternal bevel gear having a greater number of teeth than said ex`terna] bevel gear, means supporting said member to position saidinternal bevel gear in engagement with said external bevel gear, saidsupporting means serving to hold said member against rotation about itsown axis but providing for non-rotative gyratory movement of said memberabout the apex of the pitch cone of said external bevel gear as acenter, and means associated with said member for shifting the latterabout said center.

5. A power lift mechanism comprising a shaft, means for optionallyrotating said shaft, a crank shaft, an epicyclic gearing transmissionmechanism connecting said shafts, comprising an external bevel gear onsaid crank shaft, a member including an internal bevel gear having agreater number of teeth than said external bevel gear, means supportingsaid member to position said internal bevel gear to engage said externalbevel gear and holding said member against rotation about its own axis,and means on said rst shaft operatively connected to said member formoving said member so that the axis of said internal bevel geargenerates a right circular cone the axis of which coincides with theaxis of said external bevel gear.

6. A power lift mechanism comprising a shaft, means for optionallyrotating said shaft, a crank shaft in axial alignment with said firstshaft, an epicyclic gearing transmission mechanism connecting saidshafts and comprising an external bevel gear on said crank shaft, amember including an internal bevel gear having a greater number ofteeththan said external beve1 gear, means supporting said member toposition saidY internal bevel gear to engage said external bevel gearand holding said member against rotation about its own axis, aneccentric on said first shaft, a follower on said member engaging saideccentric for moving said member so that the axis of said internal bevelgear generates a right circular cone the axis of which coincides withthe axis of said external bevel gear, whereby said second shaft isrotated by the rotation of said first shaft, and means responsive to therotation of said second shaft to a certain position for interrupting therotation \of said first shaft.

7. A power lift mechanism comprising a shaft, means for optionallyrotating said shaft, a crank shaft in axial alignment with said firstshaft, an epicyclic gearing transmission mechanism connecting saidshafts and comprising an external bevel gear on said crank shaft, amember including an internal bevel gear having a greater number of teeththan said external bevel gear, means supporting said member to positionsaid internal bevel gear to engage said external bevel gear and holdingsaid member against rotation about its own axis, an eccentric on saidfirst shaft, and a follower on said member engaging said eccentric formoving said member so that the axis of said internal bevel geargenerates a right circular cone the axis of which coincides with theaxis of said external bevel gear, whereby said second shaft is rotatedby the rotation of said first shaft, and cam means rotatable with saidexternal bevel gear and operative to interrupt the rotation of saidfirst shaft.

8. A power lift mechanism comprising a shaft, means for optionallyrotating said shaft, a crank shaft in axial alignment with said iirstshaft, an epicyclic gearing transmission mechanism connecting saidshafts and comprising an external bevel gear on said crank shaft, amember including an internal bevel gear having a greater number of teeththan said external bevel gear, means supporting said member to positionsaid internal bevel gear to engage said external bevel gear and holdingsaid member against rotation about its own axis, aneccentric on saidfirst shaft, and a follower on said member engaging said eccentric formoving said member so that the axis of said internal bevel geargenerates a right circular cone the axis of which coincides with theaxis of said external bevel gear, whereby said second shaft is rotatedby the rotation of said rst shaft, means manually shiftable axially onsaid first shaft for controllably connecting the same with said rotatingmeans therefor, biased means serving to return said last named means tointerrupt the transmission of power to said first shaft, a cam carriedby said external bevel gear, and means controlled by said cam forgoverning the interruption of power to said rst shaft in accordance withthe extent of rotation of the external bevel gear on said crank shaft.

9. A power lift mechanism comprising a housing, driving and drivenshafts journaled therein in axial alignment, gear reduction meansdisposed between the adjacent inner ends of said shafts and operativelyconnecting the latter, means for driving one of said shafts including amember rotatable on said one shaft and clutch means including a secondmember optionally engageable with said first member for effecting therotation of said one shaft, manual means for clutching said memberstogether, biased means for interrupting the transmission of power fromone of said members to the other, a cam carried by the other of saidshafts, a shiftable rod supported in said housing and extending from apoint adjacent said cam alongside said gear reduction means to a pointadjacent said members, means carried at one end of said rod andengageable with said cam, and means carried at the other end of said rodfor governing the operation of said biased means in accordance with the'position of said cam.

10. The combination with a power take-off shaft, of a power liftcomprising an intermittently operable shaft disposed at right angles tothe power take-off shaft and at one side thereof, means operativelyconnecting said shafts including a pair of bevel gears and a clutchwhereby the second shaft may be intermittently operated from said rstpower take-off shaft, a crank shaft in axial alignment with saidintermittently operable shaft and disposed on the opposite side of saidpower take-olf shaft, means operatively connecting said crank shaft withsaid intermittently operable shaft comprising an external bevel gear xedon said crank shaft, a member including an internal bevel gear having agreater number of teeth than said external bevel gear, means supportingsaid member to position said internal bevel gear to engage said externalbevel gear and holding said member against rotation about its own axis,an eccentric upon said intermittently operable shaft, a followerengaging said eccentric, and an arm embracing said power take-off shaftand connecting said bevel gear member with said follower, whereby saidmember is moved so that the axis of said internal bevel gear generates acone to cause said crank shaft to be rotated by the rotation of saidinter mittently operable shaft.

11. 'I'he combination with a power take-olf shaft, of a power liftcomprising a housing, a jack shaft disposed at right angles to.saidpower take-olf shaft and at one side thereof, means for optionallyconnecting said shafts, a crank shaft journaled in said housing in axialalignment with said jack shaft and disposed on the opposite side of saidpower take-off shaft, means operatively connecting said jack shaft withsaid crank shaft comprising an external bevel gear fixed on said crankshaft, a member including an internal bevel gear having a greater numberof teeth than said external bevel gear, means in said housing supportingsaid member to position said internal bevel gear to engage said externalbevel gear and holding the same against rotation about its own axis, aneccentric on said jack shaft, a follower engaging said eccentric, a pairof arms embracing said power take-off shaft and connecting said bevelgear member with said follower, a bearing support formed integral withsaid housing and extending into the space between said arms, and abearing in said bearing support in which said power take-off shaft isjournaled.

12. The combination with a power take-olf shaft, of a power liftcomprising a housing, a jack shaft disposed at right angles to saidpower take-off shaft and at one side thereof, a bearing in said housingin which one end of said jack shaft is journaled, means for optionallyconnecting said shafts, a crank shaft journaled in said housing in axialalignment with said jack shaft and disposed on the opposite side of saidpower take-off shaft, means operatively connecting said jack shaft withsaid crank shaft comprising an external bevel gear xed on said crankshaft, a member including an internal bevel gear having a greater numberof teeth than said external bevel gear, means in said housing supportingsaid member to position said internal bevel gear to engage said externalbevel gear and holding the same against rotation about its own axis, aneccentric on said jack shaft, a

follower engaging said eccentric, a pair of arms L embracing said powertake-off shaft and connecting said bevel gear member with said follower,a bearing support formed integral with said housing and extending intothe spacebetween said arms, a bearing in said bearing support in whichsaid power take-off shaft is jour.- naled, and a second bearingsupported in said bearing support in which the other end of said jackshaft is journaled. r

13. The combination with a tractor having an opening in the body thereofand a power take. off shaft projecting through said opening, of ahousing adapted to be attached to the body of the tractor over saidopening and .having a substantially cylindrical portion disposedtransversely with respect to the axis of said power take-olf shaft, saidcylindrical portion having openings at each end, a bearingl supported inthe outer wall of said cylindrical portion in which the end of saidpower take-off shaft is journaled, a cap removably xed over each openingin said cylindrical portion, each being provided with-a bearing, a jackshaft journaled in the bearing in one of said caps, means foroperatively connecting said shafts at will, a crank shaft journaled inthe bearing in the other cap, and speed reducing gearing mechanismconnecting said crank shaft with said jack shaft. i

14. A power lift mechanism comprising a shaft, means for optionallyrotating said shaft, a crank shaft, an epicyclic gearing transmissionmechanism connecting said shafts, said mechanism comprising an externalbevel gear and an internal bevel gear, one of said gearshaving a greaternumber of teeth than the other, means supporting one gear in engagementwith the other and said other gear being mounted on said crankshaft,said supporting means serving to hold said one gear against rotationabout its own axis but providing for non-rotative gyratory movementthereof, and means for gyrating said one gear. Y

15. A power lift mechanism comprising a shaft, means for optionallyrotating said shaft, a crank shaft, an epicyclic gearing transmissionconnecting said shafts, said mechanism comprising a bevel gear on saidcrank shaft, a member including a second bevel gear, means supportingsaid member to position said second bevel gear in engagement with saidrst gear and for holding said member against rotation about its own axisbut providing for non-rotative gyratory movement of said member, one ofsaid bevel gearsv having a greater numberV of teeth than the other bevelgear, and an operative connection between said rst shaft and said memberfor causing the latter to move so tha-t the axis of said second bevelgear generates a right circular cone.

16. A power lift mechanism comprising a shaft, means for optionallyrotating said shaft, a crank shaft, an epicyclic gearing transmissionconnecting said shafts, said mechanism comprising a bevel gear on saidcrank shaft, a member including a second bevel gear, means supportingsaid member to position said second bevel gear in engagement with saidfirst gear and for holding said member against; rotation about its ownaxis but providing for non-rotative gyratory movement of said member,one of said bevel gears having a greater number of teeth than the otherbevel gear, an operative connection between said ilrst shaft and saidmember for causing the latter to move so that the axis of said secondbevel gear generates a right circular cone, means for driving said firstshaft, and means responsive to the rotation of said second shaft to acertain position for interrupting said driving means.

17. A power lift mechanism comprising a shaft, means for optionallyrotating said shaft, a second shaft in axial alignment with said iirstshaft, an epicyclic gearing transmission mechanism connecting saidshafts and comprising a bevel gear on said second shaft, a memberincluding a second bevel gear, one of said gears having a greater numberof teeth than the other, means supporting said member to position saidsecond bevel gear to engage said first bevel gear and holding saidmember against rotation about its own axis, an eccentric on said firstshaft, and a follower on said member engaging said eccentric for movingsaid member so that the axis of said second bevel gear generates a rightcircular cone the axis of which coincides with the axis of said firstbevel gear, whereby said second shaft is rotated by the rotation of saidrst shaft, means shiftable axially on said tlrst shaft fox'-controllably connecting the same with said rotating means therefor,biased means serving to return said last named means to interrupt thetransmission of power to said first shaft, a cam carried by said firstbevel gear, and means controlled by said cam for governing theinterruption of power to said first shaft in accordance with the extentof rotation of said second shaft.

NATHAN LESSER.

